The present invention relates generally to electronic test systems and more particular to systems for testing video components.
There is a growing need in the video electronics industry for test systems capable of providing a simulated color television video test signal. The luminous information of a color video signal represents shades of black and white, while the chrominance is represented by a color burst signal that establishes a phase reference together with a suppressed carrier quadrature modulation signal. The amplitude and phase of the suppressed signal deifnes a unique point and, hence, the color on a chromaticity diagram
Consistent, reliable, maintenance-free, analog instrumentation capable of producing a signal of this complexity is difficult to design and produce. An analog system requires balanced modulators that are inherently unstable. Additionally, subcarrier feed through and the need for critical phase stability and control are problems inherent in an analog implementation of a video tst system.
The video electronics industry is experiencing a trend toward the use of digital video systems and components. These systems require a test system capable of generating digitized test signals. One factor limiting the use of digital testing systems is the expense of including digital multipliers in the system.